摘要
采用射频磁控溅射(RFMS)法,在Si衬底上生长出具有(002)择优取向的MgxZn1-xO薄膜。透射光谱结果表明,与ZnO相比,MgxZn1-xO薄膜的吸收带边从378 nm蓝移至308 nm,这说明MgxZn1-xO薄膜的带隙随着Mg组分的增加而加宽。扫描电镜(SEM)能谱分析表明,薄膜中的Mg含量比靶源中的高。用不同波长的光激发得到的光致发光(PL)谱显示,在不同波长的光激励下,只出现单色蓝或绿发光峰,其它的发光峰消失,而且随着激发光波长从260 nm、280 nm到300 nm的增加,发光峰位置分别从431 nm、459 nm红移至489 nm,发光强度也显著增强。分析表明,这些发光峰与O空位有关。
MgxZn1-xO films with hexagonal structure are prepared by RF magnetron sputtering （RFMS） on Si substrates. Transmission spectra demonstrate that the absorption edge of MgxZn1-xO film has a remarkable blue shift from 378 nm to 308 nm compared with ZnO film, which shows that the band gap increases with the increase of Mg content in MgxZn1-xO film. The analysis of SEM energy spectrum displays that Mg content in MgxZn1-xO film is larger than that in the sputtering source. The photoluminescence（PL） spectra illustrate that the blue emission peak appears at wavelength 431 nm when excited by light of wavelength 260 nm. With the increase of wavelength of the excitation light from 280 nm to 300 nm, monochromatic blue and green emission peaks are generated at wavelength 459 nm and 489 nm respectively, and emission intensity shows a distinct increase in contrast to that of the emission peak at 431 nm. These PL peaks may be related to the oxygen vacancies in MgxZn1-xO film.
出处
《光电子．激光》
EI
CAS
CSCD
北大核心
2006年第5期554-557,共4页
Journal of Optoelectronics·Laser
基金
山东省中青年科学家奖励基金资助项目(2004BS01007)
